Libguestfs - Jun 2018 - lib: Convert all drive socket parameters to an absolute path

One interesting omission is that we don't allow sockets in the
abstract namespace.  The API won't let you pass these sockets because
they contain a '\0' character in the middle of the string.  Therefore
this patch doesn't need to deal with those.

However we should in future allow that, probably using the '@'
character to stand in for the NUL byte, as is used in a few other
places (eg. this is used by the ‘netstat’ program).

Rich.

---
 lib/drives.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/lib/drives.c b/lib/drives.c
index 82ef30093..7697f369a 100644
--- a/lib/drives.c
+++ b/lib/drives.c
@@ -28,6 +28,7 @@
 #include <stdbool.h>
 #include <string.h>
 #include <unistd.h>
+#include <limits.h>
 #include <netdb.h>
 #include <arpa/inet.h>
 #include <assert.h>
@@ -645,7 +646,18 @@ parse_one_server (guestfs_h *g, const char *server, struct
drive_server *ret)
       return -1;
     }
     ret->transport = drive_transport_unix;
-    ret->u.socket = safe_strdup (g, server+5);
+
+    /* libvirt requires sockets to be specified as an absolute path
+     * (see RHBZ#1588451), and it's probably a good idea anyway to
+     * check the socket exists and convert it to an absolute path.
+     */
+    ret->u.socket = realpath (server+5, NULL);
+    if (ret->u.socket == NULL) {
+      perrorf (g, _("realpath: could not convert ‘%s’ to an absolute
path"),
+               server+5);
+      return -1;
+    }
+
     ret->port = 0;
     return 0;
   }
-- 
2.16.2